Ford Repair: Rattling noise Ford Ranger, ford ranger xlt, ford ranger xlt 4x4

Question
QUESTION: Dear Brian;

I currently have a 2003 Ford Ranger XLT 4x4 (4.0L V6) with a problem.  There appears to be a rattling noise coming from the left side (I can't tell if it's front or rear).  This noise only occurs when driving the truck (i.e., it goes away when the truck is stopped).  This suggests to me that the noise is related to the driveline/brakes/suspension.  Do you know if this is a typical problem with this truck?  Any suggestion on what should be checked?

Thanks for your help,
Matt M.

ANSWER: is it a continuous rattle related to speed or only over rough surfaces

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QUESTION: It is a continuous rattle related to speed.  It occurs over all surfaces.

Answer
So I dont want to sound like I'm repeating but, your driving down the road. straight and flat and you here this noise until you come to a stop ?? If so, while your at a cruising speed 40mph or up, shift the vehicle in to neutral and let me know if it goes away